Key signature in the context of "Flat (music)"

Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. The Oxford Companion to Music describes three interrelated uses of the term "music theory": The first is the "rudiments", that are needed to understand music notation (key signatures, time signatures, and rhythmic notation); the second is learning scholars' views on music from antiquity to the present; the third is a sub-topic of musicology that "seeks to define processes and general principles in music". The musicological approach to theory differs from music analysis "in that it takes as its starting-point not the individual work or performance but the fundamental materials from which it is built."

Music theory is frequently concerned with describing how musicians and composers make music, including tuning systems and composition methods among other topics. Because of the ever-expanding conception of what constitutes music, a more inclusive definition could be the consideration of any sonic phenomena, including silence. This is not an absolute guideline, however; for example, the study of "music" in the Quadrivium liberal arts university curriculum, that was common in medieval Europe, was an abstract system of proportions that was carefully studied at a distance from actual musical practice. But this medieval discipline became the basis for tuning systems in later centuries and is generally included in modern scholarship on the history of music theory.

A time signature (also known as meter signature, metre signature, and measure signature) is an indication in music notation that specifies how many note values of a particular type fit into each measure (bar). The time signature indicates the meter of a musical movement at the bar level.

In a music score the time signature appears as two stacked numerals, such as
₄ (spoken as four–four time), or a time symbol, such as (spoken as common time). It immediately follows the key signature (or if there is no key signature, the clef symbol). A mid-score time signature, usually immediately following a barline, indicates a change of meter.

In music, modulation is the change from one tonality (tonic, or tonal center) to another. This may or may not be accompanied by a change in key signature (a key change). Modulations articulate or create the structure or form of many pieces, as well as add interest. Treatment of a chord as the tonic for less than a phrase is considered tonicization.

Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. The Oxford Companion to Music describes three interrelated uses of the term "music theory": The first refers to the "rudiments" needed to understand music notation such as key signatures, time signatures, and rhythmic notation; the second is a study of scholars' views on music from antiquity to the present; the third is a sub-topic of musicology that "seeks to define processes and general principles in music". The musicological approach to theory differs from musical analysis "in that it takes as its starting-point not the individual work or performance but the fundamental materials from which it is built."

Music theory is frequently concerned with describing how musicians and composers make music, including tuning systems and composition methods among other topics. Because of the ever-expanding conception of what constitutes music, a more inclusive definition could be the consideration of any sonic phenomena, including silence. This is not an absolute guideline, however; for example, the study of "music" in the Quadrivium liberal arts university curriculum, that was common in medieval Europe, was an abstract system of proportions that was carefully studied at a distance from actual musical practice. But this medieval discipline became the basis for tuning systems in later centuries and is generally included in modern scholarship on the history of music theory.

Shape notes are a musical notation designed to facilitate congregational and social singing. The notation became a popular teaching device in American singing schools during the 19th century. Shapes were added to the noteheads in written music to help singers find pitches within major and minor scales without the use of more complex information found in key signatures on the staff.

Shape notes of various kinds have been used for over two centuries in a variety of music traditions.

In music, two written notes have enharmonic equivalence if they produce the same pitch but are notated differently. Similarly, written intervals, chords, or key signatures are considered enharmonic if they represent identical pitches that are notated differently. The term derives from Latin enharmonicus, in turn from Late Latin enarmonius, from Ancient Greek ἐναρμόνιος (enarmónios), from ἐν ('in') and ἁρμονία ('harmony').